THE top UK civil servant behind the first independence referendum has said a second one should happen if there is a simple Holyrood majority for it in May. 

Ciaran Martin, who was constitution director at the Cabinet Office from 2011 to 2014, said the UK would no longer be a Union based on consent if Indyref2 was  blocked “by force of law” despite voters' wishes.

“If Scots vote next month for a referendum, there should be one,” he says in a report titled 'Resist, Reform or Re-Run?' published today. 

“A vote next month, or at any time after, in favour of any majority – however constituted – of MSPs elected on an explicit pro-referendum mandate, in effect puts Scotland’s consent for the Union on pause.”

He said the UK government thus faced a choice between fighting for the Union in Indyref2 or resisting by force of law, and so changing the nature of the Union.

He said third options were illusory - there was little scope for significant further devolution given so many powers had already been passed to Holyrood, while there was no public appetite for federalism. 

"There is no viable alternative model for the United Kingdom. Ultimately, the choice facing Scotlabnd, whether soon or at some point later, is between the status quo (or some variant of it) and independence." 

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Mr Martin, now a professor at the Blavatnik School of Government at Oxford University, helped negotiate the 2012 Edinburgh Agreement which underpinned the 2014 vote, and was one of just two officials in the room when Alex Salmond and David Cameron signed the document.

Prof Martin said the failure of Cameron’s government to set any rules for another referendum after the No vote meant there was now a “looming constitutional crisis”.

He said: “The current tensions are in part a result of the absence of such rules, leaving us with a profound clash of mandate versus powers, played out in the form of precedent versus slogans.”

The crisis lies in the potential clash between Westminster’s power to pass any law it chose to stop Indyref2 and the democratic mandate of Scottish voters in favour of Indyref2.

He said that, in theory, Westminster could indefinitely maintain the union by force of law.

Even if Holyrood legislated for Indyref2 without Westminster’s consent, and the Supreme Court backed it, Westminster could just pass a new law to block that vote.

In an lecture and report today, Prof Martin asks whether it would be wise to do so.

He said that if Boris Johnson stuck to his present position of dismissing demands for Indyref2 for 30 or 40 years, regardless of what Scotland voted for, it would “fundamentally” change the nature of the Union.

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He said: “In effect, it would change the Union from one based on consent, to one based on force of law.

“That would be the most profound transformation in the internal governance of the United Kingdom since most of Ireland left, almost exactly a century ago.”

He said that since the resolution of the Irish question in 1921, the British Union has been based on “an assumption of the separate and collective consent of four constituent parts, each of which is free to withdraw its consent if it wants to”. 

However the Prime Minister’s preference for a “generation” of up to 40 years between independence votes, given there was no other formal policy on it, had changed that.

“It is therefore not hyperbole to say that the UK government’s position is that there is, and will be, no lawful, democratic path to Scottish independence for an unspecified number of decades, regardless of the wishes of Scottish voters during that period.

“Hundreds of thousands of Scots who quite clearly support independence have been told throughout their lives, however old they are, that if they succeed through lawful, democratic parliamentary politics – of the type pursued by the SNP and the Greens, for example – then their objectives will be realised. 

“Now, for the first time in our lifetime, the UK government is saying that this is no longer the case, and that for an indefinite period, the lawful, democratic pursuit of a legitimate political objective cannot result in success, no matter how many people vote for it, and however often.”

He said that was not necessarily undemocratic, as some democracies such as Spain  held the state to be indivisible, but he added: “It is not hard to see how this could do terrible damage to trust, not just in government but in the Scots’ sense of participation in a union of equal partners – this being the core historic principle of the Union. 

“A union is not a union of equal partners if the bigger partner does not allow the smaller one the option to leave.”

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Prof Martin said the “difficult truth” for Unionists was that recent Westmminster trends were funnelling Scotland towards a second binary decision between union and independence.

One was previous UK Government sensitivity to Scotland being “completely abandoned”, the prime example being Brexit, which was “done to Scotland, not with it”.

That in turn had led to the Sewel Convention, under which Westminster would not “normally” legislate in devolved areas without Holyrood’s consent, also being dropped.

In addition, Scots voters had “killed off” the core Union narrative about Scots playing a disproportionate role in the UK by electing a majority of SNP MPs at three elections.

That meant there were no longer key UK cabinet figures from Scottish seats.

“The Commons no longer has its Gordon Browns, Alistair Darlings, or John Reids. This is a fundamental change to the Union that no constitutional tinkering can fix.”

Prof Martin said that if Indyref2 did take place, it should be run largely on the lines of 2014.

Trying to impose new, more onerous rules for one side to meet would be seen as cheating.

He also appealed to both sides to up their game when presenting their case in a new vote, and that both had made “implausible assertions” in 2014.

He singled out the Scottish Government’s “utterly implausible” claim that an independent Scotland would be automatically be entitled to a currency union with Sterling.

He said: “The Scottish government would need to avoid repeating the mistake of making completely undeliverable and implausible promises again.

“One unavoidable observation at this time is that it still seems unable to confront its currency conundrum: the current policy appears to be ‘sterlingisation’ in the mould of post-independence Ireland before its accession to the exchange rate mechanism. 

“That, in the eyes of many, would complicate adherence to European Union accession criteria, because the country would have no control over its currency. 

“For an administration seeking sovereignty for Scotland, the Scottish government seems, after a whole decade of deliberation, to remain peculiarly petrified of Scotland having its own currency even for a brief period.”

HeraldScotland:

The pretence that independence would led to nuclear weapons being swiftly removed from Scotland should also be dropped, he said.

“In reality, given the costs, security and safety issues around nuclear submarines, and the lack of an easy alternative location in non-Scottish UK waters, there is no practical prospect of getting nuclear weapons safely out of Scottish waters for decades to come, and a grown-up Scottish government would have to come to an arrangement with the UK government based on a recognition of that reality.

“As with the other hard choices involved in independence, the Scottish government would do well to come clean about this in a future campaign.”

He said the UK Government should also set out what a No vote would mean in practice, something it neglected to do in 2014 beyond the hastily arranged “vow” of more powers.

He suggested a No vote could come with a promise to set out the rules and pre-conditions for Indyref3, such as a minimum time period before it.

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He said: “There are huge consequences to independence. 

“Should there be a further referendum, those proposing separation would do well to avoid silly assertions to the contrary. 

“As with Brexit, independence would involve the creation of barriers that do not currently exist. There would be a land border of some sort with England – just as there has been in Ireland for a century, both before, during and after EU membership. 

“There would be, in time, different currencies, as there have been for decades across the Irish border, both during and after the UK’s EU membership.

“Nationalists would also have to address very challenging fiscal numbers, assuming a reasonable settlement of debt in the negotiations. 

“Similarly, EU membership would be likely, but not inevitable, and almost certainly not immediate. And history shows that setting up a new state is time-consuming, resource intensive, and disruptive. 

“The challenge for nationalists is to persuade voters that the disruption would be worth it.

“Equally, however, unionists should not repeat their 2014 mistake of, in effect, claiming that the enterprise of creating a successful Scottish state is impossible. 

“The history of northern Europe, with its numerous small, independent states forged from larger ones, shows that such an assertion is plainly ludicrous. 

“Nor should unionists be allowed to demand, as they did in 2014 and show every sign of doing again, that their opponents be required to provide certainty about future arrangements for an independent Scotland. 

“These are demands that are designed to be impossible to meet. 

“How an independent Scotland would fare would depend in large part on the decisions taken by its voters and by the sovereign government it elected after independence, as well as on the actions of others, such as the UK and the EU, and the circumstances of the time (no one predicted Brexit would take effect during a pandemic). 

“As the present UK government knows perhaps better than most, major constitutional change is a mixture of risk and opportunity, of certainty and unknowables. 

“Voters understand this.

“So in defending the Union it professes to cherish, the first choice the UK government might face, whether in May this year or at some point in the future, is whether it will try to maintain that Union through force of law, or to win renewed consent for it in people’s hearts and minds. It is one or the other.”

Prof Martin also said the negotiations, while long, would be driven by common interest, with Scotland’s willing to tale on a share of the UK national debt a big card in its favour.

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He concluded: "Despite all the deliberately created myths to the contrary, in the grand scheme of human affairs, the choice facing Scotland is not all that complicated.

"It’s a huge decision, of course. It’s uncertain. But it’s not complicated.

"The choice is basically this:

"Does Scotland want to be a small, independent nation, likely back in the EU but with new barriers to trade and travel with the rest of the UK; or does it wish to remain in the UK, with its own powers over some areas but subordinate to the will of the English majority on others?

"There is ample basis for Scots to make an informed choice on this question, and if they vote for the opportunity to do so, they should be given it.

"If that choice is not allowed, the United Kingdom is no longer a voluntary union."